International trends in head and neck cancer incidence rates: differences by country, sex and anatomic site

Objective: To describe trends in country and sex-specific incidence rates of head and neck cancer (HNC), focusing on changes across calendar periods.

Materials and methods: Sex and country specific rates of HNC were calculated for 1998-2002 and 1983-1987 using population-based registry data assembled by the Cancer Incidence in Five Continents (CI5) data system for 83 registries representing 35 countries. HNCs were categorized into three groups: oral cavity (including tongue and mouth), oropharynx (including tonsil and oropharynx) and other HNC (including larynx and poorly-specified tumors of the lip/oral cavity/pharynx). Age-standardized rates per 100,000 persons were calculated using the 1960 world standard population. Changes in rates between 1998-2002 and 1993-1987 were assessed.

Results: During these periods there was substantial global variation in HNC incidence trends by cancer site, country/registry and sex. Rates of oral cavity cancer increased among men and women in some European and Asian countries (Czech Republic, Slovak Republic, Denmark, Estonia, Finland, the United Kingdom and Japan). In France and Italy, rates declined among men but increased among women. Oral cavity incidence rates declined among men and women in many Asian registries as well as in Canada and the United States. Oropharyngeal cancer rates increased among both men and women in a number of European countries (Belarus, Czech Republic, Denmark, Finland, Iceland, Latvia, Norway and the United Kingdom) whereas they declined in some Asian countries. The largest increase in oropharyngeal rates was among Brazilian men. Rates of other HNCs varied substantially by country and sex.

Conclusion: From 1983-1987 to 1998-2002, trends in HNC rates differed by subtype, country and sex. Oral cavity cancer incidence rates increased in many countries with tobacco epidemics that are currently peaking and declined in areas where tobacco use peaked some time ago. In contrast, rates of oropharyngeal cancer increased in a number of countries where tobacco use has declined, perhaps due to the emerging importance of human papillomavirus infection. Continued monitoring of trends in incidence rates is needed to inform global cancer prevention strategies.